Development and application of advanced luminescence dating methods

I have been at the forefront of pioneering research in geochronology for the past 2 decades, and lead the optically stimulated luminescence (OSL) dating laboratory in the School of Earth & Environmental Sciences at the University of Wollongong. Accurate dating of key events in Earth’s history is fundamental to provide the historical framework for a wide variety of applications in the geological, biological and archaeological sciences. OSL dating has created new opportunities to investigate human interactions with their environments during the past million years, and single-grain OSL techniques can provide critical information on the stratigraphic integrity of archaeological sites. My research interests include improvements to single-grain OSL techniques and development of statistical models to more reliably date natural and archaeological deposits.

Human evolution and dispersal from Africa to Australia

Luminescence dating has had a major impact on our understanding of human settlement and migration patterns, by providing a reliable timeline for important archaeological and palaeoanthropological discoveries. I led the dating of the cave deposits on the island of Flores, Indonesia, where the skeleton of a new species of human, Homo floresiensis—nicknamed “The Hobbit”—was discovered in 2003. I have also dated the earliest known human occupation sites in Australia and, over the past few years, have collaborated with Dr Zenobia Jacobs on OSL dating of archaeological sites throughout Africa. I am currently applying single-grain OSL techniques to sites in India and on the Arabian peninsula, to piece together the timing and routes of dispersal of humans out of Africa and across South Asia.

Pleistocene environmental change and megafaunal extinction

Over the past decade, I have contributed key data to debates on megafaunal extinction events in Australia, Asia and North America. OSL dating has provided the chronological foundation to reconstruct the history of evolution and extinction of many species of prehistoric large vertebrate on these 3 continents. The ultimate causes of these extinctions are complex, but hunting by humans appears to have been the decisive factor in Australia. In addition to OSL dating of deposits containing fossil bones and teeth, I have used single-grain techniques to date frozen sediments in Siberia and Alaska that contain traces of ancient DNA. This has provided new clues to the dynamics of extinction of iconic Ice Age megafauna, such as the woolly mammoth.

Research Projects

My research spans many fields in the earth, biological and archaeological sciences, and consequently involves close collaboration with leading Australian and international researchers. The projects mentioned below are all interdisciplinary in nature, with luminescence techniques playing a key role in dating of fossils, artefacts and environmental changes.